pgvc demo for open source open mic

pgvc_demo.sql

create or replace function short_hash(long_hash character(32))
  returns character(10) as $$
  select substring(long_hash, 0, 10)
  $$ language sql; -- helper

-- pgvc "PostgreSQL Version Control"
-- it's like git for postgres!

-- some pre-existing work
select * from products;
insert into products (name, colour)
  values ('boots', 'black'),
         ('shoes', 'white');
select * from products;

-- git config
select * from git.config_user_ref('Josh');
select * from git.init();

-- git add
select * from git.add_table('products');

-- git diff
select * from git.diff();
select action, table_name, data
  from git.diff() join vc.rows using (vc_hash);

-- git log
select * from git.log();
select short_hash(vc_hash), user_ref, summary from git.log(); 

-- git commit
select * from git.commit('Add existing products');

-- git log
select * from git.log();
select short_hash(vc_hash), user_ref, summary from git.log(); 

-- git branch
select * from git.branch();
select short_hash(commit_hash), name, is_current from git.branch();

-- make a new branch
select * from git.branch('fix-boots');
select * from git.checkout('fix-boots');

-- git branch
select * from git.branch();
select short_hash(commit_hash), name, is_current from git.branch();

-- git diff
select * from git.diff();

-- update the boots
select * from products;
update products set colour = 'brown' where colour = 'black';

-- git diff
select * from git.diff();
select table_name, action, data
  from git.diff() join vc.rows using (vc_hash)
  order by data;

-- git commit
select * from git.commit('Fix boots colour');

-- git diff
select * from git.diff();

-- git diff master
select * from git.diff('master');
select table_name, action, data
  from git.diff('master') join vc.rows using (vc_hash)
  order by data;

-- current state
select * from products;

-- git checkout master
select * from git.checkout('fix-boots');

-- current state
select * from products;